Novel Numerical Methods for Strongly Coupled Quantum Field Theory and Quantum Gravity

Coordinators: David Berenstein, Jun Nishimura, Toby Wiseman, Laurence Yaffe

The physics of strongly coupled or strongly correlated systems is always challenging. However, growth of computer performance (Moore's Law,) combined with improved algorithms, have in recent years enabled noteworthy progress in our understanding of various strongly coupled theories.

One prime example is quantum chromodynamics (QCD). The QCD equation of state is a critical input in the study of heavy ion collisions, early universe cosmology, and the description of dense stars. Of particular importance is the equation of state at non-zero baryon chemical potential and the determination of transport coefficients of hot QCD. In the experimentally relevant regime, QCD is strongly coupled and analytic (perturbative) approximations are unreliable, but much progress has been made via numerical simulations of the Euclidean lattice-regularized theory. These are key ingredients in the modeling and interpretation of experimental results from heavy ion collisions at RHIC and (soon) LHC.

In a very different area, numerical techniques for studying black hole collisions and mergers in general relativity have improved tremendously in recent years. Data obtained from numerical relativity calculations are being used to create templates for gravitational wave observatories. Accurate templates are essential for distinguishing interesting signals from noise.

With the advent of gauge/string (or AdS/CFT) duality, it is now clear that, for some theories, there is a direct connection between the study of strongly coupled QFT dynamics and classical gravitational dynamics in higher dimensions. In particular, far-from-equilibrium QFT dynamics can be studied using numerical relativity in non-stationary asymptotically AdS spacetimes.

Conformal or nearly-conformal large N quantum field theories, supersymmetric lattice gauge theories, out-of-equilibrium QFT, formation and evaporation of black holes, spacetime foam, and ideas for emergent gravity, all illustrate the importance of the development of new or improved methods for studying strong coupled theories. As computers steadily become more powerful, the efforts of many people using numerical techniques to study these problems are becoming increasingly fruitful.

The purpose of this workshop is to foster communication between different communities of theoretical physicists who are working on numerical methods to attack these types of problems. The cross fertilization of ideas and finding of common ground should inspire new ways of thinking about these problems and stimulate more rapid progress.